Synthesis and characterization of dicyanate monomers containing methylene spacers

✍ Scribed by G. Anuradha; M. Sarojadevi

• Publisher: John Wiley and Sons
• Year: 2008
• Tongue: English
• Weight: 216 KB
• Volume: 110
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/app.28616

✦ Synopsis

Abstract

The bisphenols containing methylene spacer were prepared by treating eugenol/2‐allyl phenol with 2,6‐dimethyl phenol/guiacol/o‐cresol in the presence of AlCl~3~. All the bisphenols were converted to their respective cyanate esters by treating with CNBr. The structural confirmation was done by FTIR, ^1^H NMR, ^13^C NMR spectral methods, and elemental analysis. Thermal characterization was done by DSC and TGA. DSC transition shows that the T~g~ is in the range of 208–239°C. The T~g~ is highest for the cyanate ester Cy(b) with symmetric structure. The T~g~ of the cured network depends on the length and symmetry of the monomer, T~g~ being higher for shorter and the para‐substituted monomers. The T~10~ values are in the range of 364–381°C. The char yield is in the range of 47–53%. From the char yield, the limiting oxygen index (LOI) value was determined, which is used to confirm the flame retardancy of the cyanate ester resins. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008